69 



MAXIMUM. 



The daily observations made upon the weevils in the laboratory 

 supply a vast number of observations from which to select maximum 

 figures. It has been shown that under favorable conditions weevils 

 may be expected to produce an average of 6 eggs a day for a consid- 

 erable period of time. It is not surprising, therefore, that some of the 

 maximum figures obtained are very much larger than that number. 

 A few instances only will be taken from among thousands of daily 

 records. 



The highest record of eggs deposited shows that 2 small females 

 deposited together 108 eggs in 3 days, or at the daily rate of 18 eggs 

 each. This record was made on the 7th, 8th, and 9th of June, 1903. 



Table XVII. — Maximum rate of oviposition. 



Number 



of 

 females. 



Days in- 

 cluded 

 inperiod. 



Total 

 eggs de- 

 posited. 



Average 

 per day. 



Number 



of 

 females. 



Days in- 

 cluded 

 inperiod. 



Total 

 eggs de- 

 posited. 



Average 

 per day. 



2 

 1 

 2 

 5 



2 



3 

 5 

 5 

 1 



2 



108 

 76 



160 

 55 



47 



18.0 

 15.2 

 16.0 

 11.0 



11.8 



2 



1 

 2 

 3 

 5 



2 

 3 

 5 

 2 

 1 



43 



30 

 114 

 54 

 42 



10.8 



10.0 



11.4 



9.0 



8.4 



12 



16 



446 



13.5 



13 



13 



283 



9.5 



STIMULATING EFFECT OF ABUNDANCE OF SQUARES UPON EGG 



DEPOSITION. 



Four actively laying females were confined together upon a few 

 squares from September 22 till October 14, 1902, and during this 

 period they laid a total of 227 eggs, or an average of 2.37 eggs per 

 weevil per day. For the next 13 days these same weevils were isolated 

 and supplied with an abundance of squares. During this shorter 

 period the} 7 laid 236 eggs, or 4.54 eggs per female daily. 



Taking equal periods as near together as possible and using these 

 same weevils, there were deposited in 13 days upon a few squares 

 144 eggs, or 2.74 eggs per female daily, while during the following 13 

 days, with an abundance of squares, they each deposited 4.54 eggs 

 a day. 



These figures are the more striking because the stimulation was 

 plainly shown in spite of the general tendency to lay fewer eggs as the 

 weevils grow older and as the average temperature becomes lower. 



RELATION OF WARTS TO OVIPOSITION. 



When the general relation of the warts to the formation of egg 

 punctures was first recognized, an investigation was undertaken to 

 determine, if possible, in what proportion of cases the warts could be 

 traced directly to egg or feeding punctures. For this purpose a large 

 number of squares, most of which had warts, was picked from plants 



